JP2787249B2 - Water fittings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a water supply plug-in joint used for connecting an inner lining steel pipe.

[Conventional technology]

When a steel pipe is used for water supply piping, a steel pipe whose inner surface is subjected to lining processing to prevent rust is used.

Conventionally, as a joint of this inner lining steel pipe,
Screw-in type joints and mechanical joints are used, and plug-in joints known from Japanese Patent Publication No. 54-21905 are not used. Here, the plug-in joint means that the pipe body is not screwed or nuts are tightened.
This is a joint with good operability that can be prevented from falling off simply by being inserted. As shown in FIG. 5, the pipe a was inserted into the cylindrical body b of the joint to be built in the cylindrical body b. A split ring for retaining (a ring for retaining to be able to expand and contract in the radial direction by providing a notch on a part of the circumference) c was pushed out by the tubular body a, and a pulling force was applied to the tubular body a. In this case, the inner surface of the cylindrical body b is compressed in the radial direction by a tapered surface d, and a part of the split ring c bites into the outer surface of the tube a. e is a rubber packing.

This eliminates the need for on-site threading and small parts installation work, such as threaded joints and mechanical joints, in conventional plug-in joints, and protects the pipe end face despite excellent operability. This is because there was no component, and it was not possible to prevent the generation of rust on the end face of the inner lining steel pipe.

As a solution to such a problem, it is conceivable to provide a pipe end anticorrosion core used for a threaded joint for water supply or a mechanical joint inside the bayonet joint. However, in this case, unlike the screw-in type joint and the mechanical joint, the plug-in joint has a structure in which the pipe is inserted into the plug-in joint at a stretch by human power, and the pipe is inserted by a split ring or a rubber ring. Since it is performed against the elastic restoring force and frictional resistance of the packing, a considerably large force is required, and it is very difficult to control the insertion depth and insertion speed. This creates a new problem of easy breaking.

[Problems to be solved by the invention]

The present invention has been made based on the above-mentioned considerations, and the object is to provide a plug-in joint having better operability as compared with a screw-type joint or a mechanical joint, and a water supply joint (such as a screw-type joint or the like). By combining with the pipe end anticorrosion core that has been used for mechanical joints), it is possible to prevent rusting on the end face of the inner lining steel pipe even if the plug-in joint is used as a water supply joint. An object of the present invention is to solve the problem that it is difficult to control the insertion depth and the insertion speed, so that the end of the inner lining steel pipe easily breaks the pipe end corrosion protection core.

[Means for solving the problem]

The technical measures taken by the present invention to achieve the above object are as follows. That is, the water supply plug-in joint according to the present invention is a water supply plug-in joint used for connecting an inner lining steel pipe, and has a tapered surface on the inner peripheral surface of the cylindrical main body having a gradually increasing diameter inward. In addition, a first annular space portion into which a retaining ring splittable radially expandable and contractable in the axial direction and a ring-shaped packing contacting the outer peripheral surface of the inner lining steel pipe are fitted. Second
A tubular watertight portion that forms an annular space portion and that is in contact with the inner surface of the inner lining steel pipe inward of the second annular space portion, and a mounting portion for a support portion formed on an inner peripheral surface of the tubular body. An end face of an inner lining steel pipe inserted between the tubular watertight part and the inner peripheral surface of the tubular body, inside the tubular body outside the support part, the And a contact surface S that is in contact with the contact surface.

[Action]

According to the above configuration, by inserting the inner lining steel pipe into the tubular main body of the joint, the ring-shaped packing elastically contacts the outer circumference of the inner lining steel pipe to ensure watertightness, and a pulling force is applied to the inner lining steel pipe. When actuated, the retaining ring split into the first annular space is reduced in diameter by the action of the tapered surface and bites into the outer surface of the inner lining steel pipe, thereby exhibiting a retaining function.

In a state where the inner lining steel pipe is inserted into the tubular main body of the joint, the tip of the inner lining steel pipe is concealed by the pipe end anticorrosion core, so that rust generation on the pipe end face is prevented.

In particular, according to the configuration described above, the contact surface that contacts the end surface of the inner lining steel pipe is formed inside the tubular body outside the support portion that supports the mounting portion of the pipe end anticorrosion core. Therefore, since the insertion of the inner lining steel pipe into the tubular body is performed against the elastic restoring force and frictional resistance of the split ring and the ring-shaped packing, a considerably large force is required to insert the inner lining steel pipe. Although it is difficult to control the insertion depth and insertion speed,
The end of the inner lining steel pipe does not break the mounting part of the pipe end corrosion protection core.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a water supply bayonet joint according to the present invention. still,
Since the illustrated water supply plug-in joint is symmetrical, only the configuration on one side will be described.

In the figure, reference numeral 1 denotes an inner lining steel pipe comprising a steel pipe 1a and a lining layer 1b, and the tip is chamfered both inside and outside. Reference numeral 2 denotes a metal cylindrical main body of the joint, and a first annular space portion 4 having a tapered surface 3 having a gradually increasing diameter inward on an inner peripheral surface thereof, and an inner surface parallel to the axis. A second annular space portion 5 having both side surfaces perpendicular to the axis is formed in this order from the outside, and a support portion 6 made of a female screw is formed inward of the second annular space portion 5. I have.

In the first annular space 4, a retaining split ring 7, which is provided with a notch on a part of the circumference and is freely expandable and contractible in the radial direction, is fitted movably in the axial center direction. A ring-shaped support rubber 8 that restricts the movement of the split ring 7 toward the large-diameter side of the tapered surface 3 and prevents the split ring 7 from rattling is fitted in a position further inside. In the second annular space 5,
A watertight rubber ring-shaped packing 9 that elastically contacts the outer peripheral surface of the inner lining steel pipe 1 is fitted.

A tube end anticorrosion core 10 is attached to the inner peripheral surface of the tubular main body 2. The pipe end anticorrosion core 10 includes a tubular watertight portion 10a that contacts the inner surface of the inner lining steel pipe 1 and the support portion 6.
And a mounting portion 10b made of a male screw that is screwed into the cylindrical body 2. The mounting portion 10b is integrally formed of a synthetic resin material, and is mounted on the inner peripheral surface of the cylindrical main body 2 by screwing the mounting portion 10b into the support portion 6. On the inner surface of the cylindrical watertight part 10a,
A plurality of ridges 10c... Parallel to the axis direction are formed so that the above-mentioned screwing operation can be easily performed.
On the outer peripheral surface of the cylindrical watertight portion 10a, a plurality of fold portions 10d... Elastically contacting the inner surface of the inner lining steel pipe 1 are formed. In the illustrated embodiment, an O-ring 11 is fitted in an annular groove formed between the folds 10d to improve watertightness.

In addition, the cylindrical main body 2 includes the cylindrical watertight portion 10a and the inner peripheral surface of the cylindrical main body 2 on the outer portion of the support portion 6 (inside of the cylindrical main body 2 outside the support portion 6). A contact surface S that is in contact with the end surface of the inner lining steel pipe 1 inserted between them is formed.

According to this embodiment, there are the following operations or advantages. That is, in general, in a bayonet joint, since the insertion of the tube into the tubular main body is performed against the elastic restoring force and frictional resistance of the split ring or the rubber ring-shaped packing, a considerably large force is required, It may be difficult to control the insertion depth and insertion speed. However, according to the above embodiment, since the contact surface S that is in contact with the end surface of the inner lining steel pipe 1 is formed on the outer portion of the support portion 6, the inner lining steel pipe 1 may be inserted extremely vigorously. Even if there is, it does not come into contact with the contact surface S further inward.

Accordingly, there is no fear that the mounting portion 10b of the pipe end anticorrosion core 10 is moved by the tip of the inner lining steel pipe 1 and separated from the tubular main body 2.

FIG. 2 shows another embodiment of the present invention. This example is
In a linear and symmetrical water supply plug-in joint,
The present invention is characterized in that the pipe end anticorrosion cores 10 for the two inner lining steel pipes 1 inserted from both sides into the cylindrical main body 2 are formed into a symmetrical one-piece body. Further, in order to reduce the number of constituent members, the above-described ring-shaped support rubber 8 is omitted. Other configurations are the same as the previous embodiment,
The same components are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 3 shows another embodiment of the present invention. This embodiment is characterized in that the present invention is applied to an elbow-shaped water supply plug-in joint. Reference numeral 12 in the figure denotes a lining layer provided on the inner surface of the tubular main body 2. Other configurations are the same as those of the embodiment of FIG. 1, and therefore, the same components are denoted by the same reference numerals and description thereof will be omitted.

In each of the above embodiments, the support portion 6 made of a female screw is provided on the inner peripheral surface of the tubular main body 2 and the pipe end anticorrosion core 10 is screwed and attached to the support portion 6. 2
In attaching the pipe end anticorrosion core 10 to the support portion 6 provided on the inner peripheral surface of the cylindrical member, as shown in FIG. May be integrally formed. Reference numerals 13 in the figure denote anchor portions for increasing the adhesion strength of the pipe end anticorrosion core 10, and are formed so as to enter into the recessed portions formed in the support portion 6.

In each of the embodiments shown in FIGS. 1 to 4, the first annular space 4 into which the split ring 7 is fitted and the second annular space 5 into which the ring-shaped packing 9 is fitted. Are formed in this order from the outside, but the inside and outside of the first annular space 4 and the second annular space 5 may be reversed. In this case, it is possible to provide an O-ring 11 on the folds 10d of the pipe end anticorrosion core 10,
It is desirable to prevent corrosion of the split ring 7.

〔The invention's effect〕

Since the present invention has the above-described structure, the inner lining steel pipe is merely inserted into the tubular main body of the joint, and functions of retaining and watertightness are exhibited, and the tip of the inner lining steel pipe is concealed by the pipe end corrosion protection core. Therefore, it is possible to prevent the occurrence of rust on the pipe end face, and yet to form a contact face in contact with the end face of the inner lining steel pipe inside the tubular body outside of the support part supporting the mounting part of the pipe end corrosion protection core. Since the inner lining steel pipe is inserted into the cylindrical body against the elastic restoring force and frictional resistance of the split ring and the ring-shaped packing, a considerably large force is required to insert the inner lining steel pipe. Even though it is difficult to control the insertion depth and the insertion speed, the tip of the inner lining steel pipe does not crush the mounting portion of the pipe end corrosion protection core.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a water supply bayonet joint according to an embodiment of the present invention. 2 to 4 are partial cross-sectional views of water supply plug-in joints each showing another embodiment of the present invention. FIG. 5 is an explanatory view of a conventional example. DESCRIPTION OF SYMBOLS 1 ... Internal lining steel pipe, 2 ... Cylindrical main body, 3 ... Tapered surface, 4 ... 1st annular space part, 5 ... Second annular space part, 6 ... Support part, 7 ... Split ring, 9: Ring packing, 10: Corrosion protection core at pipe end, 10a: Cylindrical watertight part, 10b
…… Mounting part, S …… Contact part.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Haruki Matsuura 1 at 153 Taji Yonemachi, Kishiwada City, Osaka Japan Steel Pipe Fitting Co., Ltd. (72) Inventor Yoshiro Okazaki 1 at 153 Taji Yonemachi, Kishiwada City, Osaka Japan Incorporated (56) References JP-A 63-119996 (JP, U) JP-A 56-79790 (JP, U) JP-B 54-21905 (JP, B2) (58) Fields surveyed (Int. Cl. ⁶ , DB name) F16L 21/00-21/08 F16L 15/04

Claims (1)

(57) [Claims] 1. A water supply plug-in joint used for connecting an inner surface lining steel pipe, wherein the inner peripheral surface of the cylindrical main body has a tapered surface having a gradually increasing diameter toward the inside, and has an inner surface. A first annular space portion in which a retaining ring splittable in the radial direction is movably fitted in the axial direction, and a second ring-shaped packing in which a ring-shaped packing contacting the outer peripheral surface of the inner lining steel pipe is fitted.
A tubular watertight portion that forms an annular space portion and that is in contact with the inner surface of the inner lining steel pipe inward of the second annular space portion, and a mounting portion for a support portion formed on an inner peripheral surface of the tubular body. An end face of an inner lining steel pipe inserted between the tubular watertight part and the inner peripheral surface of the tubular body, inside the tubular body outside the support part, the A water supply plug-in joint characterized in that a contact surface S is formed so as to be in contact with the plug joint.